Question

a vector equal to two ICAP - 2 J cap - K cap and b vector equal to ICAP + 2 J cap then find the angle between a and b​

Answer 1

Given that,

Vector, $a=2i-2j-k$

Vector, $b=i+2j$

To find,

The angle between a and b

Solution,

The angle between two vectors is given by the formula as follows :

$\cos\theta=\dfrac{a{\cdot} b}{|a||b|}$

Putting all the values, we get :

$\cos\theta=\dfrac{(2i-2j-k){\cdot} (i+2j)}{\sqrt{2^2+(-2)^2+(-1)^2}\times (\sqrt{1^2+2^2)} }\\\\\cos\theta=\dfrac{2-4}{\sqrt{2^2+(-2)^2+(-1)^2}\times (\sqrt{1^2+2^2)} }\\\\\cos\theta=\dfrac{-2}{3\times \sqrt{5} }\\\\\theta=\cos^{-1}(\dfrac{-2}{3\sqrt{5} })\\\\\theta=107.34^{\circ}$

So, the angle between a and b is 107.34 degrees.

Answer 2

I hope this helps you

please mark me as brainlist